JPH0952741A - Condition for firing clinker, method for estimating cement strength and method for controlling kiln - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable even a person having no special experience, knowledge, etc., to exactly and rapidly estimate the firing conditions of clinker and cement strength by extracting the characteristics of alite crystals and belite crystals by the analysis of the microscopic images of clinker or cement and executing control in accordance with the results of the extraction. SOLUTION: The crystal images of the sample of the clinker or cement projected in a polarization microscope 1 is taken via a CCD camera 2 and a color image taking-in device 3 into a computer 5. The image processing to allow the analysis by processing the plural taken-in crystal images and executing contour line extraction is executed. The alite crystals and belite crystals are extracted in accordance with a method for discriminating alite and belite from the crystal images of the extracted contour lines. The major axis and double refractive index of the alite crystals and the diameter and lightness or double refractive index of the belite crystals are then determined. The cement strength is determined by substituting these four parameters into a concrete strength estimation equation.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for measuring clinker firing conditions and cement strength, and a kiln control method. More specifically, the characteristics of alite crystals and belite crystals by microscopic image analysis of clinker or cement. The present invention relates to a method for obtaining firing conditions of clinker and strength of cement based on extraction results and adjusting operating conditions of a kiln so as to obtain optimum firing conditions.

[0002]

2. Description of the Related Art Cement raw materials are coal-based raw materials and clay-based raw materials. Both of these raw materials become a clinker through a "raw material mixing process" and a "firing process", and a "finishing process".
To become cement. It is the firing process that has a significant effect on the quality of the cement during this process.

The cement raw material which became a mixture in the raw material mixing step is 1600 by a rotary kiln (rotary kiln).
When heat is applied to it, it causes a chemical change. At this time, cement of different quality is produced depending on the firing conditions such as heat intensity and heating rate. The quality of this cement affects the strength of the concrete, so the use of clinker cement fired under inappropriate firing conditions reduces the concrete strength.

Conventionally, the cement strength, which is the basis of concrete strength, is obtained as follows. Cement standard sand and water are kneaded in accordance with JIS R5202 to form a specimen 28
After curing for a day, the specimen is subjected to a compressive strength tester to measure its strength.

However, according to this test method, it is necessary to wait 28 days before the test can be carried out, and therefore it cannot be used as information on the firing operation of the kiln. Also, the quality of a given cement cannot be assessed immediately. Therefore, in order to solve this problem, the so-called "Ono method" is used.

[0006] This Ono method is a method developed by Dr. Yoshio Ono, and estimates the quality of cement by observing cement crystals. Ono method
The following four parameters indicating the cement firing conditions are extracted as parameters required for cement quality estimation. Major axis of alite crystal, birefringence of alite crystal, diameter of belite crystal, brightness of belite crystal

These four parameters are the thermal history (firing conditions) in the firing process of the clinker or cement.
Provide the following information regarding: Major axis of alite crystal: temperature rise rate Birefringence of alite crystal: maximum temperature Diameter of belite crystal: high temperature time Brightness or birefringence of belite crystal: cooling rate

The extracted parameters are evaluated in four levels to obtain parameter evaluation points, and the evaluation points are substituted into the following "cement strength estimation formula" to obtain the strength of cement on the 28th day. To decide.

28-day strength = 254.46 + 6.38 × (evaluation point of major axis of alite crystal) + 4.01 × (evaluation point of diameter of belite crystal) + 21.90 × (of birefringence of alite crystal Evaluation points)
+21.51 x (evaluation point of lightness or birefringence of belite crystal)

In the estimation formula, the coefficient of the parameter relating to the color of the cement crystal is considerably larger than the coefficients of the other parameters. Therefore, it is required to accurately extract the birefringence index of the alite crystal and the brightness or birefringence parameter of the belite crystal. In addition, good quality cement in the Ono method means that the long diameter of alite crystals is small, the birefringence of alite crystals is large, the diameter of belite crystals is large, and the brightness or birefringence of belite crystals is large. Is.

[0011]

The Ono method is highly evaluated as a highly accurate measuring method of cement strength. However, this method has the following problems. (1) Accurate analysis is impossible unless you are an expert in analysis with the following conditions. a. Being knowledgeable about mineral crystals and having an excellent visual sense for microscopic observation, b. Having accumulated analysis experience and constantly engaged in measurement work and cultivating analysis technology. However, even in such an expert's measurement, the analysis results are not always the same due to differences in experience and ability of each expert. Sometimes.

(2) Although the analysis time is extremely shortened as compared with the conventional method of obtaining the cement strength by the specimen,
However, the analysis time is long and it is not possible to meet the demand for knowing the cement strength within the day.

In view of the above circumstances, the present invention makes it possible for a person who does not have any special experience to accurately determine the firing conditions and cement strength of the clinker and in a short time. The purpose is to control the kiln to optimum operating conditions based on cement strength.

[0014]

SUMMARY OF THE INVENTION The present invention includes an image capturing step of capturing a crystal image of a clinker or cement sample displayed on a polarization microscope into a computer; and processing and contouring a plurality of crystal images captured in the step. An image processing step for extracting and analyzing lines, and a crystallographic image classification step for extracting alite crystals and belite crystals based on the alite-belite discrimination method from the crystal images of the contour lines extracted in the step; A four-parameter measurement for determining the major axis and birefringence of the alite crystal based on the parameter measurement method of the alite crystal, and for determining the diameter and brightness or birefringence of the belite crystal based on the parameter measurement method of the belite crystal A clinker firing condition and a method for estimating cement strength, characterized by comprising:
It is.

According to the present invention, an image capturing step of capturing a crystal image of a clinker or cement sample projected on a polarization microscope into a computer; and processing of the crystal image captured in the step to extract a contour line to enable analysis. An image processing step; a crystal image classification step of extracting alite crystals and belite crystals based on the alite-belite discrimination method from the crystal images of the contour lines extracted in the step; and alite crystal parameter measuring method A four-parameter measurement step for determining the major axis and birefringence of the alite crystal based on the above, and the diameter and brightness or the birefringence of the belite crystal based on the method for measuring the parameters of the belite crystal; And a strength estimation process for obtaining cement strength by substituting it into a strength estimation formula; Estimation method of firing conditions and cement strength clinker is.

The present invention includes an image capturing step of capturing a crystal image of a clinker or cement sample projected on a polarization microscope into a computer; and processing of a plurality of crystal images captured in the step to extract a contour line for analysis. And an image processing step for extracting a crystal image of alite crystals and belite crystals based on an alite belite discrimination method from a crystal image of a contour line extracted in the above step; and parameters of alite crystals Obtaining the major axis and birefringence of the alite crystal based on the measurement method, and
A four-parameter measurement step for obtaining the diameter and brightness or the birefringence of the belite crystal based on the parameter measurement method for the belite crystal; and an evaluation point conversion step for obtaining the evaluation points for the four parameters based on a parameter evaluation table; From the evaluation points, the temperature rising rate, the maximum temperature, the high temperature holding time, and the cooling rate are calculated based on the evaluation score table, and the estimated pattern of firing conditions is calculated; and the estimated pattern is compared with the standard pattern in the standard firing state. And a control step of adjusting the kiln operating conditions so that the estimated pattern becomes the standard pattern, and a kiln control method,
It is.

According to the present invention, an image capturing step of capturing a crystal image of a clinker or cement sample displayed on a polarization microscope into a computer; and processing the crystal image captured in the above step to extract a contour line for analysis. An image processing step; a crystal image classification step of extracting alite crystals and belite crystals based on the alite-belite discrimination method from the crystal images of the contour lines extracted in the step; and alite crystal parameter measuring method A four-parameter measurement step for determining the major axis and birefringence of the alite crystal based on the above, and for determining the diameter and brightness or birefringence of the belite crystal based on the method for measuring the parameters of the belite crystal; Evaluation point conversion process for obtaining evaluation points based on the evaluation table; Based on the process of obtaining the temperature rising rate, maximum temperature, high temperature holding time, cooling rate, and obtaining the estimation pattern of the firing conditions; the evaluation point of each parameter is substituted into the concrete strength estimation formula to obtain the concrete strength. And a control step for adjusting kiln operating conditions based on a comparison between the estimated pattern and a standard pattern in a standard firing state and a comparison between the estimated cement strength and the target cement strength. Control method.

[0018]

BEST MODE FOR CARRYING OUT THE INVENTION An image of a clinker crystal on a slide of a polarizing microscope is captured by a computer (image capturing step), and this image is processed into an analyzable state (image processing step). Then, after this image processing, the alite crystal image and the belite crystal image are extracted while observing the image (crystal extraction process), and the major axis and birefringence of the alite crystal, the diameter and the lightness or the birefringence of the belite crystal are extracted. The refractive index and is measured (parameter extraction process).

This parameter is converted into an evaluation point based on a predetermined evaluation table of each parameter, and
Estimated strength is calculated from the cement strength estimation formula and the evaluation points (parameter evaluation step). Further, the temperature rising rate, the maximum temperature, the high temperature holding time and the cooling rate are obtained from the evaluation points of the respective parameters based on the evaluation score table, the estimated pattern of the firing conditions is obtained, and the estimated pattern and the estimated 28-day strength are calculated. Adjust the operating conditions of the rotary kiln based on the values (kiln control stroke).

Image capturing step: A sample of clinker or cement is placed on a slide by a predetermined method, and the slide is set on a polarizing microscope. The crystal image observed with a polarization microscope is loaded into a computer and the image data is processed. At this time, if the captured crystal image is different from that observed with a microscope, the analysis result will be greatly affected. Therefore, it is necessary to be careful when capturing the image. Therefore, as the image capturing means, specifically,
The polarization microscope is equipped with a CCD camera, which is connected to a computer via a color image capturing device so that the crystal image of the sample can be read directly into the computer.

Image processing step: noise removal of the crystal image captured by the computer is performed. Here, the noise removal is to remove the image noise contained in the image so that the alite crystals and the belite crystals can be observed accurately. Further, as a premise of parameter measurement, binarization of a crystal image, labeling, crystal restoration, deletion of minute portions, and contour line extraction are sequentially performed.

Binarization is a black and white image for distinguishing the target crystal from the background.
In the belite crystal, those satisfying the specific conditions of R (red) G (green) B (blue) are set to 1, other ones are set to 0, alite crystals and belite crystals are made black, and other It makes things white.

Labeling is to give one image and each image regarded as one image an independent number to distinguish each image from other images.

The restoration of a crystal means filling a holed portion of a crystal image or combining crystal images which are divided into a plurality of images into one.

The deletion of a minute portion means that a minute crystal contained in a binarized image and unnecessary for analysis is cut off.

The extraction of the contour line means that the pixels constituting the outer circumference of each crystal are used as the contour line and the contour line is extracted. In this way, a plurality, for example, 300 to 400
Process individual crystal images.

Crystal extraction process: (1) Alite crystals and belite crystals are classified based on the alite belite determination method. This discriminating method classifies crystal images according to the variance or absolute deviation rate of the center of gravity of the crystal. That is, the center of gravity (Xm, Ym) of the contour line of each extracted crystal is obtained, and the shape factor representing the degree of difference between the contour line shape and the circle is defined by one of the following, and this value is used to determine the alite. Classify as crystal, belite crystal or other.

Shape factor s = (√Σ (x ₁ −x ₀ ) ² + (y ₁
−y ₀ ) ² / N × (√x ₀ ² + y ₀ ² ) or shape factor s = Σ | x ₁ −x ₀ | / N × x ₀ + Σ | y ₀ −yi
| / N × y ₀ i) Shape coefficient ≦ α ii) α <shape coefficient ≦ β iii) Shape coefficient> β where α and β are parameters.

(2) The major axis and birefringence of the alite crystal are obtained based on the method for measuring the parameters of the alite crystal. i) The method for determining the major axis of the alite crystal in this method is as follows. That is, the alite crystals are identified by the crystal tilt angle and the ridge line extraction, and the crystals that satisfy the ridge line angle = φ ± δ or ψ ± δ of the alite crystals classified in (1) above are regarded as alite crystals. Then, the major axis is obtained from the relationship between the length of the ridgeline and the geometrical ratio of the ideal crystal.

As another method, the color image of the alite crystal once distinguished from the alite crystal is binarized again, and the condition of the threshold value of RGB at the time of binarization is relaxed to approximate the ideal crystal pattern. By adopting the method of finding the crystal, it is possible to prevent the underestimation of the major axis due to the change of the color which is likely to occur around the crystal and to perform the measurement more accurately. A characteristic diameter is obtained by performing statistical processing from this diameter distribution.

Feature major axis is extracted by utilizing the particle size distribution (weighted) of alite crystals. Data on the major axis of each alite crystal obtained in the above i) is created, and a statistical index characteristic of this distribution is extracted to determine the characteristic alite major axis. This characteristic major axis is used as the major axis of the alite crystal as a parameter.

Ii) The method for obtaining the birefringence of the alite crystal in this method is as follows. That is, a. The birefringence is measured as follows using an RGB (red green blue) table. The retardation is measured at each point in each crystal by the following method. Here, the retardation means an optical path difference between two polarized lights orthogonal to each other in the crystal, and the birefringence can be obtained by dividing the optical path difference by the crystal thickness.

B. Statistical processing is performed from the birefringence data of each alite crystal obtained in the previous section, and the maximum birefringence is extracted to obtain the characteristic birefringence. This characteristic birefringence index is used as the birefringence index of the alite crystal.

C. Measure the crystal thickness to calculate the birefringence. That is, the crystal thickness is calculated from the width of the alite crystal, but when measuring the crystal width, the crystal width including the void is used. Here, the interstitial substance is a substance interposed between the alite crystal and the belite crystal.

(3) The diameter and brightness of the belite crystal are obtained based on the method for measuring the parameters of the belite crystal. i) The method for determining the diameter of the belite crystal in this method is as follows. The characteristic diameter of belite crystals is extracted and corrected by using the particle size distribution of belite (weighted). That is, the diameter of each of the belite crystals obtained by the classification of the above item (1) is measured, and statistical processing is performed on the diameter data to obtain the characteristic diameter. Belite crystals are darker at the periphery than at the center, and therefore, when measured optically, the characteristic grain size is smaller than it actually is. Since there is a geometrical similarity to this, the true characteristic diameter is obtained by multiplying by a correction coefficient. This true characteristic diameter is used as the diameter of the belite crystal as a parameter.

As another method, instead of using the correction coefficient, the color image of the belite crystal once distinguished from the belite crystal is binarized again, and the condition of the RGB threshold value at the time of binarization is set. By loosening, it is possible to measure a more accurate diameter of the individual crystals. A characteristic diameter is obtained by performing statistical processing from this diameter distribution.

Ii) The method for obtaining the lightness of the belite crystal in this method is as follows. The brightness of a belite crystal is measured by measuring RGB at all points of each belite crystal, and using any one of R (red), G (green), and B (blue) or the sum or average of RGB. The lightness is measured and systematically processed to obtain the darkest lightness. The true darkest brightness is used as the parameter for the brightness of the belite crystal. Since it is possible to measure the birefringence of the belite crystal, the birefringence may be used instead of this brightness. The method for obtaining this is the same as the method for measuring the birefringence of alite crystals.

Parameter evaluation process: With respect to the four parameters obtained as described above, a range is set for each parameter in advance, the range is divided into four stages, and an evaluation table (table from 1 to 4) is given. Each point is given based on 1). In this evaluation table, the major axis of alite crystal is Bur.
ning rate (temperature rising rate), birefringence of alite crystals is Max temp (maximum temperature), diameter of belite crystals is Bur.
The ning time (high temperature holding time) and the brightness or birefringence of the belite crystal indicate the state of Cooling rate.

[0039]

[Table 1]

Parameter evaluation points are based on expert measurements. The strength of the cement (28-day strength) is determined by substituting the parameter values with scores into the "cement strength estimation formula" below.

28-day strength = 254.46 + 6.38 × (evaluation point of major axis of alite crystal) + 21.90 × (evaluation point of birefringence of alite crystal) + 4.01 × (of diameter of belite crystal) Evaluation point) + 21.51 x (evaluation point of brightness or birefringence of belite crystal)

Using the evaluation score table (Table 2), the values of the parameters with the evaluation scores (scores) are used to obtain an estimated pattern of clinker firing conditions.

[0043]

[Table 2]

Next, in order to confirm the firing conditions by comparing the estimated pattern with the standard pattern in the standard firing state, and to fire a clinker having a good quality, some kiln operating methods most suitable for the current situation. , The standard condition is controlled by using the blended raw material input amount that controls the firing conditions of the clinker, the fuel supply amount and air amount in the burner, the kiln rotation speed, and the like.

The rate of temperature rise is not an indication from the inlet of the kiln, but is an average rate of rise displayed conversely from the maximum temperature and the high temperature holding time at the highest temperature portion of the combustion temperature in the kiln. The cooling rate is a display from the maximum temperature to the cooling start temperature and is an average cooling rate.

In the heat history of the clinker, basically, when the major axis of the alite crystal is small, the heating rate is high,
If the birefringence of alite crystals is high, the maximum temperature is high,
When the belite crystal has a large diameter, the high temperature holding time is long, and when the belite crystal has a transparent lightness, the cooling start temperature is high.

The heat history of the clinker has, for example, the following patterns, and the kiln operation control corresponding to each pattern is performed. a: the long diameter of the alite crystal is large, the birefringence of the alite crystal is low, and the diameter of the belite crystal is large,
When the lightness of the belite crystals is yellowish brown, low heat,
Long flame firing, low amount of f.CaO (unreacted lime) and small weight (Pattern 1). b: the long diameter of the alite crystal is small, the birefringence of the alite crystal is high, and the diameter of the belite crystal is small,
If the lightness of the belite crystals is transparent, high heat, short flame firing, f. The amount of CaO (unreacted lime) is slightly high and the weight is high (pattern 2).

C: When the long diameter of the alite crystals is small, the birefringence of the alite crystals is low, and the diameter of the belite crystals is small, and the lightness of the belite crystals is yellowish brown, low heat, long heat Flame burning (pattern 3). d: the major axis of the alite crystal is large, the birefringence of the alite crystal is high, and the diameter of the belite crystal is large,
When the lightness of the belite crystal is pale yellow to yellow, it means high flame and long flame firing (Pattern 4).

[0049]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the present invention will be described with reference to the accompanying drawings. Preparation process of cement sample and the like: The lump clinker discharged from the rotary kiln is crushed and then screened to obtain a sample (cement sample). At this time, the lump clinker has a diameter of, for example, 20 mm, and the sieve mesh has a diameter of, for example, 60 μm. The crystal of the sample has a cluster of crystals called a group crystal, but this group crystal can be removed by making the size of the above-mentioned sieve mesh.

Take a small amount of this sample with a measuring spoon,
Place it in the center of the slide and flatten it. 5-7 from there
Make a cement sample of square mm and remove the remainder. Next, one drop of the immersion liquid is dropped on the cover glass, and the immersion liquid and the sample are thoroughly mixed using the cover glass. After carefully overlaying the cover glass and the slide so that no air enters, the slide is placed on the autostager of the polarizing microscope 1. This auto stager is a device that changes the range of the cement sample that enters the field of view of the microscope, and can be moved left and right and back and forth. The magnification of the polarization microscope is appropriately determined according to need, but for example, 200 times is adopted.

Image capturing step P1: The computer 5 captures the crystal image of the cement sample on the preparation.
Various methods can be considered as this import method,
Here, as shown in FIG. 2, C provided in the polarization microscope 1 is used.
A method is adopted in which image data is directly captured by the computer 5 via the CD camera 2 and the color image capturing device 3 connected to the CCD camera 2.

This image capturing method is superior to other methods, for example, a method of capturing a micrograph of a crystal of a cement sample into a computer by a scanner. That is, in this method, since it is not necessary to develop the photograph, the problem of color unevenness that occurs during the development of the photograph does not occur, and accurate information can be obtained.

Image processing step P2: As described above, the polarization microscope 1 is connected to the color image capturing device 3,
Therefore, observation can be performed by looking at the monitor. In order to distinguish the crystal image observed with the microscope 1 from the background, binarization processing is performed. Here, the binarization process is
Pixels f (i, j) ε {0. . Two
55} to a binary pixel g (i, j) ε {0,1}.

The binarization formula is as follows. In addition, the threshold is RGB of blue and yellow which are cement crystals.
It is determined from the gradation value.

This binarization processing is performed by sending to the computer 5 the crystal image captured with 256 gradation values for each of RGB. A binarized crystal image is shown in FIG. 3, in which AK indicates an alite crystal.

An independent number is assigned to each of the completely binarized crystal image and the image regarded as one image. This is called labeling.

The binarized image also contains many fine crystals unnecessary for analysis. Therefore, in order to extract only the necessary crystal parts, minute crystals or crystal fragments that do not reach a certain area are discarded. This is called deletion of minute parts.

Cement crystals include those with holes and those with division. To repair such crystals,
The following filling process is performed. (1) While scanning the screen from the upper left to the upper right, -1 is assigned to pixels having a value of 0 and sandwiched by the same label. (2) Regarding pixels having a value of −1 while scanning pixels from upper right to upper left a. If the upper and lower pixels are assigned to the same label, the same label is assigned to this image. b. If 0 is assigned to either the upper or lower pixel, or both pixels, 0 is assigned to this pixel.

(3) Recount the number of pixels having the same label for each area. FIG. 4 shows an image after the minute portion is deleted and the crystal is repaired.

Pixels forming the outer periphery of each crystal of the crystal in which a minute portion has been deleted and the crystal has been repaired are defined as contour lines,
The following processing is performed to extract this contour line. If there are 0 pixels on either the top, bottom, left, or right of the labeled pixels while scanning the pixels from the upper left to the lower right, multiply these labeled pixels by -1 to obtain a negative value for the value of the contour pixel. To In order to extract only the pixels with a negative value, 1 is assigned to the pixels with a negative value and 0 is assigned to the other pixels. An image in which the contour line is extracted in this way is shown in FIG. A plurality of pieces thus captured, for example, 300 to 40
Process 0 crystal images.

Crystal image extraction step P3: Alite crystals, belite crystals, etc. are discriminated from the crystal images binarized by image processing and the contour lines are extracted based on the alite belite discrimination method. The procedure for identifying each crystal is as follows. a: Obtain the center of gravity of the crystal image. b: Obtain the average distance from the center of gravity to the contour. c: Obtain the variance or standard deviation of the distance from the center of gravity to the contour.

D: Normalize the variance or standard deviation by the average of distances. e: Compare the standardized variance or standard deviation with an experimentally determined threshold value, and classify into alite crystal and belite crystal or other according to the comparison result. f: A crystal image ridgeline classified into alite or other is obtained, and the angle of the ridgeline falls within the range of either 45 ° ± 135 ° ± φ (φ: angle threshold). The shape of the crystal image is determined to be alite or other based on the similarity with the ideal crystal image.

Extraction process P of alite crystal parameters
4: Obtain the major axis and birefringence of the alite crystal based on the parameter measurement method of the alite crystal. (1) The major axis of the alite crystal in this method is obtained as follows. The major axis of the alite crystal is estimated from the ratio of the major axis and the major side of the ideal crystal model by measuring the major axis as a substrate. The ideal crystal model of the alite crystal is as shown in FIG. 6, and there is a certain empirically determined ratio relationship among the major axis Ld, the major side Lo, the minor axis Ls, and the crystal thickness.

The actual form of the alite crystal is as follows. Colorless and transparent hexagonal or fragmental polyhedron, large particles 60 μm or more, medium particles 15-40 μm, small particles 10
It can be roughly classified into μm or less, and develops blue or yellow when observed with a polarizing microscope. Approximately 135 when emitting blue light
If it emits yellow light, it means that it is tilted at about 45 °.

It is known from the theory of clinker generation that the major axis distribution has two peaks. Therefore, from a plurality of samples (cement samples), create a "histogram of the frequency of major axis and number of pieces" as shown in FIG.
The average of the two peaks p1 and p2 is extracted as the major axis.

The method of extracting the long diameter is not limited to this, and a method adopted by an expert may be used, for example. That is, the expert uses the “major axis-number frequency × histogram of the cube of the major axis” as shown in FIG. 8 and sets the longer peak p3 of the two peaks p3 and p4 of this gram as the major axis of the alite crystal. Extract.

(2) The birefringence of the alite crystal in this method is determined as follows. That is, in the computer 5, the color information of the sample (cement crystal) is RG.
It is expressed as a B gradation value. Therefore, this color information is extracted from the relationship between the retardation and the RGB gradation value, the retardation is measured using the relationship between the two, and the double bending rate is obtained using the separately measured crystal thickness.

This method does not require the operation of inserting and removing the λ inspection plate, which is performed in the case of microscopic observation with human eyes.
The labor of operation can be reduced. Here, the λ test plate refers to a crystal plate that produces a fixed retardation that is fixed between crossed Nicols in order to facilitate the measurement by the interference color of the retardation. An example of the relationship between the retardation and the RGB gradation value is shown in FIG.

Here, Retardation
Is the optical path difference in the crystal of two polarizations orthogonal to each other when observed by a polarizing microscope, and the birefringence can be obtained by dividing by the thickness of the crystal. This retardation R
Can be reproduced by observing a quartz device called a quartz edge with a polarization microscope. FIG.
0 shows a conceptual view of the microscope field of view 20. Around the alite crystal AK, a reference color S different from the color ac of the alite crystal S
It is C. In addition, K shows a crystal.

As shown in FIG. 11, the quartz edge 1
Reference numeral 0 is composed of a quartz main body 11 having an inclined surface 12 and a wedge-shaped slider 13 sliding on the inclined surface 12, and when the slider 13 slides in the direction of the arrow, its thickness h Changes, and the retardation of light with respect to CL changes. The quartz edge 10 has 1000 to 350
There is a scale (not shown) up to 0, and the retardation R is calculated from the value a of this scale using the following formula. R = 0.9497 (a-1595)

The birefringence Aβ of an alite crystal is obtained by dividing the retardation R by the estimated thickness Ds of the alite crystal, that is, Aβ = R / Ds. The estimated thickness Ds of the alite crystal is calculated by multiplying the minor axis Ls of the crystal including the pores of the alite crystal by an empirical ratio, or using the same value as the ratio of the ideal crystal, the major axis. Ask from.

Statistical processing is performed from the birefringence data of each alite crystal obtained as described above, and the maximum birefringence is extracted to obtain the characteristic birefringence. In order to prevent the variation when the maximum value is adopted from the distribution of birefringence as the characteristic birefringence, the birefringence which occupies the upper 5 to 10% of the area of the birefringence distribution curve is regarded as the maximum value. , Adopted as a characteristic birefringence.

Extraction process P of parameters of belite crystal
5: Determine the diameter and brightness of the belite crystal based on the method for measuring the parameters of the belite crystal. (1) The diameter of the belite crystal in this method is obtained as follows. The diameter of the belite crystal is obtained by the following equation using the average distance between the center of gravity and the contour line obtained by extracting the crystal. Diameter = (average distance between center of gravity and contour line) x 2

The diameter distribution of the belite crystals is treated in the same manner as the extraction of the major axis of the alite crystals. Therefore, a "diameter-frequency of number x histogram of cube of diameter" is created and the characteristic diameter of the belite crystal is extracted. However, the belite crystal is darker in the peripheral portion than in the central portion, and therefore the characteristic grain size is smaller than the actual grain size when optically measured. Therefore, the obtained particle size does not always match the true particle size.

However, this belite crystal is similar to the ideal crystal model of the belite crystal. Therefore, by utilizing this property, the characteristic diameter is multiplied by a predetermined correction coefficient to obtain the true characteristic diameter. This true characteristic diameter is used as the diameter of the belite crystal as a parameter. As shown in FIG. 12, the ideal crystal model BK is a spherical body having a diameter BD, the diameter of the crystal is generally 10 to 30 μm, and a yellow color is formed when observed with a polarizing microscope. HL indicates a thin parallel line.

(2) The lightness of the belite crystal in this method is obtained as follows. The brightness of the belite crystal is the brightness when the crystal emits light from the light source of the microscope. The evaluation of this brightness is Clean (colorless), faint
yellow (light yellow), yellow (yellow), Amber (yellowish brown)
The four-step evaluation is performed.

This brightness is expressed by 256 gradation values for each of RGB. For all the dots of each belite crystal that was the object of measurement, the brightness of each dot was calculated from the RGB value by the brightness formula: brightness = (Red + Blue + Green) / 3, and the average was calculated as the brightness of the belite crystal. A histogram shown in FIG. 13 is created from the obtained lightness, a standard deviation σ is obtained, and a range of 2σ to 3σ is adopted for the bright direction (plus direction). The value in this range is the brightness as a parameter.

The lightness of the belite crystal was set in the same manner as the birefringence of the alite crystal, and the retardation and RGB
It is possible to extract the lightness as a birefringence index using the relationship of gradation values. Therefore, it is possible to use the birefringence of the belite crystal instead of the lightness of the belite.

4-parameter evaluation point conversion P6: (1) Parameter evaluation method. Each of the four parameters is divided into four levels, and a score (evaluation point) is given based on the evaluation table (Table 1) in which a rank of 1 to 4 is given. Here, the parameter evaluation points are based on the measured values of the experts.

The clinker firing conditions (heat history) are estimated from the value of each parameter with scores based on the evaluation table (Table 1), and the estimated pattern is obtained. For example, if the measured values of the four parameters are the major axis of alite crystal 40 to 50 μm, the birefringence of alite crystal 0.005 to 0.006, the diameter of belite crystal 20 to 25 μm, and the brightness of belite crystal are transparent. The evaluation points of 1 are the major axis of the alite crystal, the birefringence of the alite crystal, the diameter of the belite crystal of 3, and the brightness of the belite crystal of 4.

The respective evaluation points are evaluated as follows based on the evaluation score table (Table 2). Temperature rising rate is 20 ° C /
The maximum temperature is 1530 ° C, the high temperature holding time is 5 to 6 minutes, and the cooling rate is more than 50 ° C / minute.

An estimated pattern D14 shown in FIG. 14 is prepared using these firing conditions. In FIG. 14, S
Is a standard pattern and shows the firing conditions in the standard state, that is, when the evaluation points of all parameters are 3. BR indicates a temperature rising rate area in the standard state, BT indicates a high temperature holding time area in the standard state, and CR indicates a cooling rate area in the standard state.

Strength estimation process P7: The 28-day strength is obtained by substituting the parameter values with the scores into the "cement strength estimation formula" stored in the computer 5. 28-day strength = 254.46 + 6.38 × 1 + 4.01 × 3 + 21.90 × 2 + 21.51
× 4 = 402.71 (kg / cm ² )

Kiln control process P8: The estimated pattern of the clinker firing conditions and the standard pattern are compared, and the calculated 28-day strength of cement and the target cement strength are compared, and the estimated pattern becomes the standard pattern. ,And,
The amount of blended raw material that controls the firing conditions of the clinker, the amount of fuel supply and air in the burner, and the kiln rotation speed are adjusted so that the cement strength becomes the target cement strength.

In FIG. 14, since the firing temperature is insufficient, control is performed such that the burner flame temperature is increased and the kiln rotational speed is slightly increased.

A second embodiment of the present invention will be described with reference to FIG. The estimated pattern D15 in FIG. 15 is created by obtaining evaluation points (scores) based on the four parameters obtained in the same manner as in the above embodiment. The evaluation points of each parameter are as follows. Alite crystal major axis 2, alite crystal birefringence 3, belite crystal diameter 4, belite crystal brightness 1 28 days intensity = 254.46 + 6.38 × 2 + 4.01 × 4 + 21.90 × 3 + 21.51
× 1 = 392.37 (kg / cm ² )

In this embodiment, since the firing zone tends to be deep (toward the center of the kiln) and there is poor cooling, operation control such as pulling out the burner to the inlet side or slightly reducing the kiln torque is performed.

A third embodiment of the present invention will be described with reference to FIG. The estimated pattern D16 in FIG. 16 is created by obtaining evaluation points (scores) based on the four parameters obtained in the same manner as in the above-mentioned embodiment. The evaluation points of each parameter are as follows. Alite crystal major axis 4, alite crystal birefringence index 3, belite crystal diameter 2, belite crystal brightness 4 28 days intensity = 254.46 + 6.38 × 4 + 4.01 × 2 + 21.90 × 3 + 21.51
× 4 = 439.86 (kg / cm ² )

In this embodiment, since the front side (outlet side) tends to be burnt and the high temperature holding time is insufficient, the burner is slightly thrust toward the center of the kiln, and the burner frame is adjusted to lengthen the flame. .

Of course, the present invention can be used not only for clinker as a sample to be observed but also for cement.

[0091]

EFFECTS OF THE INVENTION Since the present invention is configured as described above, even a person having no special knowledge and experience has four parameters, that is, the major axis and birefringence of the alite crystal, and the bead, like an expert. The diameter and brightness or birefringence of the light crystal can be obtained, the firing conditions and the cement strength can be obtained, and the kiln operation can be appropriately controlled. Furthermore, 1) It is possible to reflect the operation of the rotary kiln in near real time. That is, it becomes possible to manage the steady operation state, study recovery measures for abnormal states, and operate indicators of transitional states such as product type switching, fuel switching, and raw material switching. 2) Variations in the measurement results due to differences in the knowledge ability of the measurer are eliminated, and accurate measurement results can be obtained. 3) The quality of cement can be estimated accurately in a short time. Incidentally, according to the present invention, the cement strength could be known within 20 minutes to 1 hour. 4) The kiln operation can be appropriately controlled based on the estimated pattern of the firing conditions and the 28-day cement strength estimated value. 5) Recently, various fuels such as wastes have been used as the kiln fuel in addition to heavy oil and pulverized coal. According to the present invention, the thermal characteristics of the fuel used can be known.
Therefore, it becomes possible to appropriately manage the heat of the fuel such as the used waste.

[Brief description of drawings]

FIG. 1 is a flowchart showing a first embodiment of the present invention.

FIG. 2 is a perspective view showing an embodiment of the present invention.

FIG. 3 is a diagram showing a binarized image.

FIG. 4 is a diagram showing a crystal image of a binarized image after the crystal is repaired and a minute portion is deleted.

FIG. 5 is a diagram showing an image after a contour line is extracted.

FIG. 6 is a perspective view showing an ideal crystal model of alite.

FIG. 7 is a diagram showing a “major axis-number frequency histogram”.

FIG. 8 is a diagram showing “major axis-number frequency × histogram of cube of major axis”.

FIG. 9 is a diagram showing a relationship between retardation and RGB gradation values.

FIG. 10 is a conceptual diagram showing a microscope field of view.

FIG. 11 is a perspective view showing a quartz edge.

FIG. 12 is a perspective view showing an ideal crystal model of belite.

FIG. 13 is a diagram showing a brightness histogram of a belite crystal.

FIG. 14 is a diagram showing standard patterns and estimated patterns of clinker combustion conditions.

FIG. 15 is a diagram showing a second embodiment of the present invention and is a diagram showing a standard pattern and an estimated pattern of clinker combustion conditions.

FIG. 16 is a diagram showing a third embodiment of the present invention and is a diagram showing a standard pattern and an estimated pattern of clinker combustion conditions.

[Explanation of symbols]

 1 Polarizing microscope 2 CCD camera 3 Color image capture device 5 Computer

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI Technical indication location G01N 21/21 G01N 21/21 Z 21/23 21/23 (72) Inventor Ichino Manabu Saitama Ishizaka, Hatoyama-cho, Hiki-gun, Tokyo Denki University (72) Inventor Hiroyuki Yaguchi Ishizaka, Hatoyama-cho, Haiki-gun, Saitama Prefecture (no house) Masato Nakama (72) Inventor Masato Nakama Taito-ku, Tokyo 6-16-19 Ueno Inside Technical Ark Co., Ltd.

Claims (11)

[Claims] 1. An image capturing step of capturing a crystal image of a clinker or cement sample displayed on a polarization microscope into a computer; and processing a plurality of crystal images captured in the step to extract a contour line to enable analysis. An image processing step; a crystal image classification step of extracting alite crystals and belite crystals based on the alite-belite discrimination method from the crystal images of the contour lines extracted in the step; and alite crystal parameter measuring method And a four-parameter measurement step for determining the major axis and birefringence of the alite crystal based on the above, and for determining the diameter and brightness or birefringence of the belite crystal based on the method for measuring the parameters of the belite crystal. Characterizing clinker firing conditions and concrete strength estimation method. 2. An image capturing step of capturing a crystal image of a clinker or cement sample displayed on a polarization microscope into a computer; and an image processing for processing the crystal image captured in the step to extract a contour line for analysis. With the process;
A classification process of crystal images for extracting alite crystals and belite crystals based on the alite-belite discrimination method from the crystal images of the contour lines extracted in the process; and the alite based on the parameter measurement method of the alite crystals A four-parameter measurement step for determining the major axis and birefringence of the crystal, and for determining the diameter and brightness or birefringence of the belite crystal based on the method for measuring the parameters of the belite crystal; A clinker firing condition and a method for estimating cement strength, which comprises: 3. The clinker firing according to claim 1, wherein the image capturing step directly inputs a crystal image to a computer through a CCD camera connected to a polarization microscope and a color image capturing device. Conditions and method for estimating cement strength. 4. The contour processing is performed in the image processing step after performing noise removal processing, binarization processing, labeling processing, crystal restoration processing, and minute portion deletion. Or a method for estimating clinker firing conditions and cement strength as described in 2. 5. An alite-belite discriminating method in a classification process of crystal images obtains a center of gravity of each extracted contour line,
The method for estimating clinker firing conditions and cement strength according to claim 1 or 2, wherein a shape coefficient representing a degree of difference between a contour line shape and a circle is determined by a value defined by a definition formula. 6. A parameter measurement method for an alite crystal in a 4-parameter measurement process, wherein a histogram of data of major axis of each alite crystal is formed, and a statistical index characteristic of the distribution of the histogram is extracted. The major axis of the artificial alite crystal is defined as the major axis.
Method for estimating clinker firing conditions and cement strength described. 7. A parameter measurement method for an alite crystal in a four-parameter measurement process, wherein a birefringence index is obtained from the relationship between the retardation of an erato crystal and the crystal thickness, and statistical processing of the birefringence index of each alite crystal is performed. The clinker firing condition and the method for estimating cement strength according to claim 1 or 2, wherein the maximum birefringence is extracted and the characteristic birefringence is used as the birefringence. 8. A method for measuring a belite crystal in a four-parameter measurement process, wherein the characteristic diameter is obtained by statistically processing the diameter data of each belite crystal, and the characteristic diameter is multiplied by a correction coefficient. The calcination conditions of clinker and the method for estimating cement strength according to claim 1 or 2, wherein the characteristic diameter of is the diameter. 9. A method for measuring the parameters of a belite crystal in a four-parameter measurement process, wherein R of all points of each belite crystal is used.
It is characterized in that GB is measured, characteristic lightness is measured using one of R, G, and B, or the sum or average of RGB, and the darkest lightness obtained by statistically processing them is taken as lightness. The method for estimating the clinker firing conditions and the cement strength according to claim 1 or 2. 10. An image capturing step of capturing a crystal image of a clinker or cement sample displayed on a polarization microscope into a computer; and processing a plurality of crystal images captured in the step to extract a contour line for analysis. An image processing step; a crystal image classification step of extracting alite crystals and belite crystals based on the alite-belite discrimination method from the crystal images of the contour lines extracted in the step; and alite crystal parameter measuring method A four-parameter measurement step for determining the major axis and birefringence of the alite crystal based on the above, and for determining the diameter and brightness or birefringence of the belite crystal based on the method for measuring the parameters of the belite crystal; An evaluation score conversion process for obtaining an evaluation score based on the evaluation score; based on the evaluation score list from the evaluation score of each parameter Then, the temperature rising rate, the maximum temperature, the high temperature holding time, and the cooling rate are obtained, and the process of obtaining an estimated pattern of firing conditions is compared; the estimated pattern is compared with a standard pattern in a standard firing state, and the estimated pattern is the standard pattern. And a control step for adjusting the kiln operating conditions so that 11. An image capturing step for capturing a crystal image of a clinker or cement sample projected on a polarization microscope into a computer; and an image processing for processing the crystal image captured in the step to extract a contour line and analyze it. Process; a process of classifying crystal images for extracting alite crystals and belite crystals based on the alite-belite discrimination method from the crystal images of the contour lines extracted in the above process; and based on a parameter measurement method of the alite crystals A four-parameter measurement step for determining the major axis and birefringence of the alite crystal, and for determining the diameter and brightness or birefringence of the belite crystal based on the method for measuring the parameters of the belite crystal;
An evaluation point conversion process of obtaining an evaluation score of the four parameters based on a parameter evaluation table; a temperature increase rate, a maximum temperature, a high temperature holding time, and a cooling speed are calculated from the evaluation score of each parameter based on the evaluation score table, and firing is performed. A process of obtaining an estimated pattern of conditions; a strength estimation process of substituting the evaluation points of the respective parameters into a concrete strength estimation formula to obtain concrete strength; a comparison between the estimated pattern and a standard pattern in a standard firing state and the estimated cement A kiln control method comprising: a control step for adjusting kiln operating conditions based on a comparison between strength and target cement strength.